The flywheel has long been recognized as a potentially useful energy storage device for use in many different applications. Perhaps one of the most important potential applications is in vehicles such as buses and automobiles, where the flywheel can be used to manage the power to the drive wheels. Flywheel modified buses have been tested in urban public transport. However, flywheel energy storage devices have not come into general use in buses or in other transportation vehicles. Thus far flywheels have not met the required levels of performance, especially in the areas of total energy stored, total system weight, energy efficiency, rotor longevity, cost, and safety.
Thus there is a need to provide a flywheel energy storage system that has maximized energy storage capacity, minimized system weight, minimized containment weight, improved energy efficiency when used in transportation, improved rotor longevity, and improved safety performance.